PHP timestamp - first day of the week

If Monday is your first day:

$ts = mktime(0, 0, 0, date("n"), date("j") - date("N") + 1);

If you think Monday is the first day of the current week...

$ts = strtotime('Last Monday', time());

If you think Sunday is the first day of the current week...

$ts = strtotime('Last Sunday', time());

If it is the monday you're looking for:

$monday = new DateTime('this monday');
echo $monday->format('Y/m/d');

If it is the sunday:

new DateTime('this sunday'); // or 'last sunday'

For further information about these relative formats, look here "PHP: Relative Formats"

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